Acrylonitrile polymer solutions containing morpholine derivatives



Patented Apr. 13, 1954 ACRYLONITRILE POLYMER SOLUTIONS CONTAINING MORPHOLINE DERIVA- TIVES Robert C. Harrington, Jr., Kingsport, Tenn., as-

signor to Eastman Kodak Company, Rochester, N. Y., a corporation of New Jersey No Drawing. Application November 8, 1951,

Serial No. 255,550

'7 Claims.

1 This invention relates to a new composition of matter comprising polyacrylonitrile (polymerized vinyl cyanide), and copolymers, interpolymers, and graft polymers of polyacrylonitrile in solution in, or plasticized with, compounds selected from the group consisting of phosphoryl morpholine, thionyl morpholine and thiophosphoryl morpholine.

The invention also relates to shaped articles produced from polyacrylonitrile polymers incorporated with these compounds and to methods of making such articles.

Since polymers of acrylonitrile, including the homopolymers, graft polymers, interpolymers, and copolymers thereof, are known to possess many desirable chemical and physical properties, such as insolubility in the common organic so1- vents, including acetone, methanol, ethanol, ethyl ether, ethyl acetate, benzene, toluene, ethylene dichloride, etc., insensitivity to these solvents, and unusual toughness and moisture regaining properties, many attempts have been made to find solvents which could be utilized to spin these polymers into fibers. Inorganic salts, such as zinc chloride, lithium bromide and sodium sulfocyanide, have previously been proposed for this purpose. However, fibers spun byextrusion of these solutions into coagulating baths which are non-solvents for polyacrylonitrile or ,copolymers or acrylonitrile, such as water, dilute acid solutions, glycerol, etc., usually contain large amounts of these salts. The fibers containing these salts are not uniform and possess poor physical properties, and even where it is possible to eliminate these salts from the fiber, the fibers become weak, spongy or brittle. Some of these salts have the further undesirable property of causing the fibers to have a tacky consistency, which results in the individual filaments sticking together to give an extremely brittle, inflexible fiber having many of the characteristics of a monofilament. U. S. Patents 2,404,713 and 2,404,728 propose to use various organic compounds as solvents for polymers of acrylonitrile and show how solutions of these polymers can be used to spin fibers which do not possess the undesirable properties that result from the use of inorganic salts.

I have now discovered that polymers of acrylonitrile, where the polymer molecule contains a major proportion, and preferably at least 80% of polyacrylonitrile, can be incorporated with, as in solution, phosphoryl morpholine, thionyl morpholine, or thiophosphoryl morpholine, and that these solutions can be used to advantage in the 2 preparation of fibers, films, molded objects, an other shaped articles. These solvents are cheaply and easily prepared from readily available raw materials and are stable when heated, to 150 C. and maintained at this temperature for as long as 30 minutes. They also show good shelf life in storage.

It is an object of my invention to provide a new class of solvents for polyacrylonitrile, and copolymers, interpolymers and graft polymers of polyacrylonitrile in which a major proportion, and preferably at least of thepolymer is polyacrylonitrile. A further object of the invention is to provide solutions of polymers of acrylonitrile in these new solvents, which solutions can be used advantageously in the wet and dry spinning of fibers and in the formation of other shaped articles. Still another object of the invention is to provide improved methods of forming synthetic filaments, molded articles and the like from acrylonitrile.

These and other objects of the invention will be more apparent after consideration of the fol lowing specification.

The solvents and plasticizers with which the invention is concerned include the following group of compounds:

Phosphoryl morpholine Thionyl mcrpholine Thiophosphoryl mcrpholine These compounds are prepared as follows:

Example I A total of 153 gms. (1 mole) of P001; is placed in a ii-neck flask fitted with a condenser and stirrer. To this, 261 gms. (3 moles) of morpholine are added slowly with vigorous stirring of the reaction mixture which is kept at a temperature not higher than 10 C. during this time. The solid product which is formed is heated to its melting point, and held there for 15-20 minutes to complete the evolution of HCl. At the end of this time, the reaction product is recrys- 3 tallized from ethyl alcohol, and needles of fairly pure phosphoryl morpholine melting at 164- 165 C. are obtained. This compound is an excellent solvent for acrylonitrile polymers and copolymers ofathe .classes previouslyrdescribed.

Example II One hundred and nineteen grams (1 mole).of

thionyl chloride is dissolved in 500 ml. of ethylene dichloride and added to aiiwellecooled-3eneckflask fitted with a stirrer an'd condenser.-' Asolution of 179 gms. (2 moles) of morpholine dissolved in 250 ml. of ethyleneadiohloride.issthen added slowly to the thionylzchloride'solution the Example III A total of 169 arms. (1 mole) ofithicphosphoryl chloride is addedislowly. to 261'gms. (3: moles) of hilled morpholine' placed in a- 3neckx.fiasl :hav n'g -an eflicient'stirrer-fiend reflux condenser. 1 In his reacti'on'yit is necessary towarmitheareac- 1i; ion mixture in order to: complete thetaddition OT' PSCIa since a'solid is soonuformed .in the 1 reaction vessel. Y This is :done' carefully, and the solid obtained is further-warmedto .remove 'HCl. 's'olidtcompoun-d is recrystallized from alcof'hol to 'givewhite needles offairlypure thiophospho'ryl morpholine melting at 171-'-173.C.. This I: compound is an excellent solvent for the classes ofpolymers and copolymersf previously described.

It is apparent that the preparation ofathecom- H p'ounds of' theabove examples is'quite simple, usince'itisonly necessary to react morpholine with POCls, PSCls or SOC12 withsmorpholineinthe -fcoldyheat the: resulting: mixture-for. about 15 minutes, and then purify by one recrystallization. These compounds are inexpensive andeasily -ebtained on a normal market. Ordinarily, most compounds are made by a more involved process of reactions andi subsequent distillations, and

even then may not beof'high purity. However, the compoundsdisclosedherein as solvents show good solvent power with. little purification.

The polymer solutions are prepared by adding the powdered polymer or copolymer to the warm liquid solvent and-stirring until solution is complete. Alternatively;*theisolvent and the polymer can be intimately mixed by using a Waring Blender, mixing rolls or the like, followed by heating, preferably under pressure. perature to which the solvent mixture is heated may vary from about 100 C. to 250 C. depending on-.the solvent. Polymer .sol-utions intended for various uses and having different viscosities and other characteristics-may be prepared by varying .the solids content of the solutions.

" Polyacrylonitrile. solutions. prepared by jusing '"the solvents set forth aboveforzn filaments, when extruded througha filament forming orifice'into a suitable coagulating medium in either a wetjor dry'process. .As is well .known, .these processes involve. the use of evaporative orsolvent exhaust- .ing media such as alcohol, steam, air, or, others which arewell known in the art. v

Examples of the use of solutions of polyacrylo-e The teminitrile in the new solvents for making filaments are as follows:

Example A About 10 parts by weight of powdered polyacrylonitrile-are stirredintdlooparts of phosphoryl=morpholine which hadbeen heated to about 170 C. Any temperature from the melt- 1:iing point of the solvent up to about 225 C. would .be .satisfactpry. A smooth, pourable solution results. 7 r

"This solution is extruded at about 200 C. through a spinneret into a coagulating bath of *isopropLhoi maintained at about 25 C. to form 5 a -fi'lainent' 0).?t1'll'82td of polymeric acrylonitrile.

Such filaments may be given such further known .f-:.;plrysicaltreatment such as stretching, treatment 2-.with various liquids, and the like, as may be desired. Films are produced when the hot solution is poured onto a warm surface, such as glass, followedby immersion in ahot solvent for the5morpholine compound, forexamplegat aboutslOfKC.

' Other examplescould be given using:. thej:other compounds set forth in Examples IeIII-,.-but: since they areusedin: the same mannereaseasetiorth in Example A, it would be repetitious toiinclude them herein. it is to be understoodethatrzthe examples which have been .setcforthrarerugiven merely in an illustrative -'sense,:.as the-invention I is :not limited thereto.

" Polyacrylonitrile. solutions made irraccordance with the invention can-alsobe extruded. astapes,

-' bars, rods and other desired :configurations.

5 After use of the solvents of:..the inventioncthey may. be readily recovered: fromthe-coagulating medium. Where thesolvent is arsolidmormally,

-* distillation. This ease ofrecovery; by permitting re-useprenders this class ofsolvents quite geoc- J -nomical.

i Molded articles may beformed from thesolu- .1 tions' described above-by the use of any s suitable pmol'din'g procedureknown. to the art.

. The -solvents I which: :.are :.the subject. matter of rmy invention have been found to be highly usa vful. .andaadvantageous: over mal'lyi 'v reviously 1noticeableadegradation.

. Various 2 types. of 2-, 'modifying agents can---be added. to, the solutions. made as: describedabove, 1f01' example, 7 proteins, cellulose. :organica-gla'cid 2:; esters-,1: cellulosexethers, :polyam-ides,

polyesters,

vinylpolymers, :etc.

f. *Icl'aim:

-. a As a .newucomposition of .matter, a; polymer of: acrylonitrile containing. in.the'rpolymeramole- :cule. at-least ,a-"major proportionbywweightr'of poly-acrylonitrile, incorporated with azcompound selectedfrom the; group consisting ofrjphosphoryl morpholine, thionyl; morpholine. andrv ithiqphosphoryl morpholine.

2.--As a newcomposition of matter, a polymer ofacrylonitrile containing in 'thepolymen moleculeat-least amajor proportiombyrweight of .poly-acrylonitrilal :dissolved in a .-,compoundi selected .fromthe .group consistingv ofieph osphoryl mor holina- .thionyl..m0rpholine. :and thiophose 751.phoryl.morpholine. 7

6. A composition of matter according to claim 3 wherein the solvent is thiophosphoryl morpholine.

7. A plasticizer for acrylonitrile polymers containing in the polymer molecule at least a major proportion of poly-acrylonitrile, comprising a compound selected from the group consisting of phosphoryl morpholine, thionyl morpholine and thiophosphoryl morpholine.

No references cited. 

1. AS A NEW COMPOSITION OF MATTER, A POLYMER OF ACRYLONITRILE CONTAINING IN THE POLYMER MOLECULE AT LEAST A MAJOR PROPORTION BY WEIGHT OF POLY-ACRYLONITRILE, INCORPORATED WITH A COMPOUND SELECTED FROM THE GROUP CONSISTING OF PHOSPHORYL MORPHOLINE, THIONYL MORPHOLINE AND THIOPHOSPHORYL MORPHOLINE. 